Asians are dominating in visitor and international student numbers and in most family-migration categories to New Zealand.

Over a period of increased departure of New Zealand citizens, especially to Australia, this could change the country's social fabric faster than anticipated, Massey University sociologist Paul Spoonley says.

"Asians have moved from being 'a significant number' to 'dominating' most immigration categories," Professor Spoonley said.

Over the 2011-12 period, New Zealand suffered its first net migration loss since 2001 - but the combined Asian temporary and permanent arrivals increased.

China by far outnumbered the rest in the visitor and student-visa categories, and had approval numbers more than three times higher than India and the UK in the family-sponsored and parent categories.

Despite the UK still being the biggest source country for permanent residents, Professor Spoonley noted, the combined total from China, India and the Philippines more than doubled the British.

Professor Spoonley said despite the rapid rise in numbers, it would be decades before Asians would outnumber Pakeha - but he said strains were starting to show.

"We also haven't been very good at telling New Zealanders about the positive aspects of immigration."

He said it was "hard for people to feel positive" about immigration during times of high unemployment and economic downturn.

In an annual Asia New Zealand Foundation survey released last month, just half felt Asian immigration was positive and a third felt immigrants were taking jobs away.

An Auckland Grey Power director also wrote to the Auckland Council saying the region's older residents felt "under serious threat from the rapid and huge changes in size and ethnic-mix projections".

Professor Spoonley said New Zealand was good at recruiting migrants, but poor in assisting with settlement. Compared to Australia or Canada, support systems and structures for new migrants were lacking here.

New Zealand First says current family migration policy favours the Chinese, and wants a review of the family reunion policy.

Under Immigration's "centre of gravity" rule, a parent can be sponsored if the number of adult children living in New Zealand was equal to or exceeded those in any single country. With China's one-child policy, nearly all China nationals who are permanent residents would therefore be eligible to sponsor parents.

"The double-whammy impact of Immigration's 'centre of gravity' paired with China's one-child policy was a disproportionate advantage to parents applications from China," said NZ First MP Denis O'Rourke.

"Parents from China filled up more than half the total parent-reunion quota, and parent reunion migrants are eligible for superannuation at age 65 after 10 years of residence."

He said sponsored migrant parents were a burden on health care, superannuation, housing and welfare.

Last July, the parent category was re-launched as a two-tier scheme, where applicants needed at least $65,000 and prove they could bring $500,000 to New Zealand to be in tier one, where applications would be processed faster.

"It appears the new policy has increased the parent application from China even more, with most just transitioned from 'centre of gravity' to tier one," Mr O'Rourke said.

Figures he obtained showed applicants from the UK had dropped from 1157 to 637, but Chinese applications rose from 4891 to 5830.

Immigration New Zealand is looking to international students as "an important source of skilled migrants", and China, being the largest source country for international students, could soon overtake the UK in the category. Over the past decade, one in five international students obtained permanent residence visas within five years.

Last year, 38 per cent of skilled immigrants were former international students, with India overtaking Britain as the main source of skilled immigrants.

Professor Spoonley said "being more generous" with family migration would encourage more skilled migrants to come and remain here, and he did not agree parents were a burden to New Zealand.

"Studies have shown that, overall, migrants contribute far more to the economy and what they pay in taxes than what they take, including these parents," he said.

"They play the role of caregiver to their grandchildren, allowing their children to return to work, and provide the sense of family that would keep their migrant children rooted here."

Nearly 40 per cent of Aucklanders were born overseas and projections show that Asians could make up 30 per cent of the city's population within eight years.

Net migration is expected to remain negative at least until the middle of next year.

Mother wishes her mum could stay on and help

Expectant mother Dong Suk Jang wants to sponsor her 67-year-old mother to remain in New Zealand.

The 34-year-old former preschool teacher is expecting her third child any day and is dreaming of being able to return to work.

"I am so happy my mother has flown in from Korea to be with me for the birth, but I wish she could stay here permanently," said Mrs Jang, who moved to New Zealand 10 years ago.

"It is really difficult when you have no extended family support, and no family member to help in looking after the children."

She said that in Korea there was also a culture of engaging live-in domestic helpers, which was not the norm here.

However, because Mrs Jang has four other siblings in South Korea, under Immigration's "centre of gravity" rule she cannot sponsor her mother for permanent residence.

Her mother, Ul Yeol Kim, 67, arrived last week on a visitor's visa and is planning to remain for two months.

Mrs Jang's husband, Andy Kwak, is a hairdresser who works six days a week, and the couple have two children, Sun Gyo Kwak, 4, and Suna Kwak, 2.

During the births of their first two children, Mr Kwak had to take a few weeks off work to help with duties at home.

"With mum here this time, he can carry on working because mum will be helping with the cooking, cleaning and looking after the kids," said Mrs Jang.

"If she was here permanently, I am very sure that I too will be able to go back to work instead of having to wait until the kids grow up."

Massey University sociologist Paul Spoonley said relaxing the rules on family migration would encourage more migrants to move and remain in New Zealand.

He said sponsored parent migrants provided "childcare" and "family support" and indirectly contributed to the economy as their children would be able to return to the workforce.

NZ First MP Denis O'Rourke said they were a burden on healthcare, superannuation, housing and welfare systems.